In a known automobile seat, the back support adjustment mechanism includes an elastic adjustment element in the from of a hoop that is essentially deformable because of its shape. Special drive devices are provided for the actuation medium of the adjustment element that firmly engage with longitudinally-displaceable counter-elements on the hoop. Such actuation mediums must be adjusted either using a motor or by hand.
Further, an automobile seat with a tiltable seat back is known whose seat base includes a central seat area and at least one side wing whose shape in the use position extends upward or outward with respect to the shape of the central seat area. The side wing of the seat base may be moved downward with respect to the central seat area so that the upper shape of the side wing projects slightly more with respect to the central seat area than when in the use position. The ability for the side wing to be lowered provided in this known solution allows tilting the seat back forward onto the seat base in such manner that the tilted seat back is horizontal. One disadvantage of the known solution is that the side wings are formed separately from the central seat area, and must be adjusted separately. Such a solution is relatively expensive and does not allow the seat surface to be largely formed as one piece.
It is also already known to tilt seat backs without side projections forward onto the seat base. When the front side of the seat back rests on the upper side of the seat base, the rear side of the seat back in such designs is not horizontal, but rather increasingly oblique forward. In order for the seat back to achieve horizontal position, the upholstery of the seat back and seat base in such designs are pressed together to the extent that the desired horizontal position results. The seat back is then secured in the horizontal position achieved by exertion of force.
Starting from this state of the art, it is the challenge of the invention to provide an automobile seat of the known type so that its construction is simple, and that its seat back may be tilted forward from the use position into the tilted non-use position with horizontal alignment of the seat back rear side.